The battle between the ABC and conservative commentator Chris Kenny is officially over – and the verdict is unequivocal. Game, set and match: Kenny.

The Australian Communications and Media Authority (ACMA) ruled on Friday that the infamous Chaser sketch depicting Kenny having sex with a dog breached the ABC's editorial policies, overruling an earlier ABC verdict that the segment was legitimate. ACMA found the sketch, aired on TheHamster Decides program last September, breached the ABC's "harm and offence" standard, which states: "Content that is likely to cause harm or offence must be justified by the editorial context."

The authority said the sketch was clearly satirical but the digitally altered image of Kenny fornicating with a dog was not justified. The segment was "intrinsically likely to have caused high level of offence".

ACMA also suggests in its verdict that the ABC board should reflect on whether its code of practice is operating effectively when it comes to harm and offence.

The present standards on harm and offence serve to "complicate and obscure rather than simplify or clarify", it found.

Complaints about whether the segment carried appropriate classifications and warnings were dismissed.

The ACMA verdict overrules the ABC complaint department finding last October that the segment did not breach the broadcaster's editorial policies. The ABC's audience and consumer affairs division found the skit would have offended many viewers but was legitimate satire.

In April, ABC managing director Mark Scott issued a formal apology to Kenny for the sketch. Earlier this month, the ABC reached a settlement with Kenny, who sued the broadcaster for defamation, that involved paying him $35,000 in damages and apologising to him on-air.

Kenny said earlier this month he sued the ABC to show that the broadcaster should not be able to silence or intimidate its critics.